Sometimes there is need to modify order or columns data in CSV-formatted datalogs, for example if charting software accepts only specific formatting.
For small datasets this can be done manually, but there is quicker way to do this job if we use Python environment.

Python is also useful for processing large datasets. Common need of this is preparation raw datasets for graphing and analysis. Often all thousands of points are not required, so short app below does some data fiddle with CSV input and produce reduced dataset, suitable for interactive graph creation, even in realtime with frameworks like D3.js